'\" te
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.TH NET_ISVALIDCHECKSUM 9F "May 1, 2008"
.SH NAME
net_isvalidchecksum \- verify layer 3 and layer 4  checksums
.SH SYNOPSIS
.nf
#include <sys/neti.h>

\fBint\fR \fBnet_isvalidchecksum\fR(\fBconst\fR \fBnet_data_t\fR \fInet\fR, \fBmblk_t\fR *\fImb\fR);
.fi

.SH INTERFACE LEVEL
illumos DDI specific (illumos DDI).
.SH PARAMETERS
.ne 2
.na
\fB\fInet\fR\fR
.ad
.RS 7n
value returned from a successful call to \fBnet_protocol_lookup\fR(9F).
.RE

.sp
.ne 2
.na
\fB\fImb\fR\fR
.ad
.RS 6n
the \fBmblk\fR structure holding a packet that is the subject of this query.
.RE

.SH DESCRIPTION
The \fBnet_isvalidchecksum()\fR function verifies the layer 3 checksum (and, in
some case, the layer 4 checksum) in the packet. If possible, fields that are
used by hardware checksum'ing are examined rather than  manually verifying that
the checksums are present for packets received from a network interface.
.sp
.LP
For both \fBIPv4\fR and \fBIPv6\fR, \fBTCP\fR, \fBUDP\fR and \fBICMP\fR
(including \fBICMPV6\fR for \fBIPv6\fR) layer 4 checksums are currently
validated.
.SH RETURN VALUES
The \fBnet_isvalidchecksum()\fR function returns:
.sp
.ne 2
.na
\fB-1\fR
.ad
.RS 6n
The network protocol does not support this function.
.RE

.sp
.ne 2
.na
\fB0\fR
.ad
.RS 6n
The packet does not contain partial checksums.
.RE

.sp
.ne 2
.na
\fB1\fR
.ad
.RS 6n
The packet does contain partial checksums.
.RE

.SH CONTEXT
The \fBnet_isvalidchecksum()\fR function may be called from user,  kernel, or
interrupt context.
.SH ATTRIBUTES
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
Interface Stability	Committed
.TE

.SH SEE ALSO
.BR attributes (7),
.BR net_ispartialchecksum (9F),
.BR net_protocol_lookup (9F)
